Serological evaluation of Neospora caninum in pregnant women treated at referral center for prenatal screening in Mato Grosso do Sul, Brazil / Avaliação sorológica de Neospora caninum em gestantes atendidas em centro de referência para triagem pré-natal em Mato Grosso do Sul, Brasil

Abstract Neospora caninum is an obligate intracellular protozoan with canids (Canis domesticus, Canis lupus dingo, Canis latrans, Canis lupus) as its definitive hosts. The objective of this study was to detect anti-N. caninum antibodies in pregnant women seen at referral center for prenatal screening in the state of state Mato Grosso do Sul, Brazil. A total of 188 serum samples from pregnant women provided by the Instituto de Pesquisa, Ensino e Diagnósticos da APAE de Campo Grande (IPED/ APAE) were subjected to IFA test and western blot analysis. The samples were divided into three groups: 23/99 samples from the seropositive group for toxoplasmosis were positive for anti-N. caninum IgG antibodies, and 9/99 positive for IgM; in the HIV group, 7/33 were positive for IgG; and in the HIV+toxoplasmosis group, 13/56 were positive for IgG and two positive for IgM. The seropositivity for IgG was assessed by western blot by testing 43 IFA test positive samples using rNcSRS2 (Nc-p43) as antigen. The serological results of the present study suggest that exposure of these pregnant women to the parasite N. caninum and presence of IgM antibodies are indicative of recent infection. Further studies are needed to establish the possibility of active infection.

Resumo Neospora caninum é um protozoário intracelular obrigatório que possui os canídeos (Canis domesticus, Canis lupus dingo, Canis latrans, Canis lupus) como seus hospedeiros definitivos. O objetivo deste trabalho foi detectar anticorpos anti-N. caninum em gestantes, atendidas em centro de referência para triagem pré-natal, em Mato Grosso do Sul, Brasil. Um total de 188 amostras de soro de gestantes, cedidas pelo Instituto de Pesquisa, Ensino e Diagnósticos da APAE de Campo Grande (IPED/ APAE), foram submetidas ao teste de RIFI e western blot para a detecção de anticorpos anti-N. caninum. As amostras foram divididas em três grupos: 23/99 amostras do grupo soropositivo para toxoplasmose demonstraram positividade para anticorpos IgG anti-N. caninum e 9/99 positivos para IgM. No grupo HIV 7/33 apresentaram positividade para IgG. No grupo HIV+Toxoplasmose 13/56 apresentaram positividade para IgG e duas para IgM. A soropositividade para IgG foi avaliada por western blot, testando 43 amostras positivas para RIFI, usando-se rNcSRS2 (Nc-p43) como antígeno. Os resultados sorológicos do presente estudo sugerem exposição dessas gestantes ao parasita N. caninum e a positividade para anticorpos IgM são indicativos de infecção recente. Mais estudos na área são necessários para estabelecer a possibilidade de infecção ativa.

Molecular Detection and Seroprevalence of Babesia microti among Stock Farmers in Khutul City, Selenge Province, Mongolia

Babesiosis is an emerging tick-borne disease in humans worldwide; however, little is known about the frequency of infection or prevalence of this disease in other parts of the world, excluding North America. In this study, we aimed to investigate Babesia microti infection frequency in a human population in Mongolia. One hundred blood samples were collected from stock farmers living in Khutul city of Selenge province, Mongolia. The sera and DNA from blood samples were evaluated for the presence of B. microti infection by using indirect fluorescent antibody (IFA) tests and PCR. The positive detection rates obtained using the IFA tests and PCR assays were 7% and 3%, respectively. This study is the first to detect of B. microti infections based on antibody seroprevalence or PCR assays for the presence of B. microti DNA in a Mongolian population.

Distribution of dengue virus types in Aedes aegypti in dengue endemic districts of Rajasthan, India.

Background & objectives: Dengue haemorrhagic fever (DHF) is the major cause of sustained morbidity/ mortality among human cases of dengue in dengue endemic areas of Rajasthan. Screening of mosquitoes collected from disease endemic settings and typing the virus could provide signifi cant epidemiological information for prospective risk of DHF. We therefore carried out a study on different dengue virus types as occurring in fi eld collected Aedes aegypti mosquitoes from four dengue endemic districts of Rajasthan, India. Methods: Adult Ae. aegypti were collected from the human dwellings of urban, peri-were collected from the human dwellings of urban, urban and rural settings of four dengue endemic districts of Rajasthan, India. The fi eld collected adults were fed on 4 per cent glucose solution and kept in the laboratory for 3-4 days. The adult fi eld collected Ae. aegypti, were subjected to indirect fl uorescence antibody test (IFAT) following standard procedure. Commercially acquired monoclonal antibodies against DEN types 1, 2, 3 and 4 were used. The remnants of IFA test subjected mosquitoes were made into viral suspension which was inoculated into the cell culture medium and mouse brain to confi rm the presence of virus as shown by IFA test. Results: Of the 498 adult Ae. aegypti tested, 78 (15.6%) were positive by IFA test. Among urban areas, desert area (Jodhpur) showed highest (21.6%) mosquito infectivity followed by 7.1 per cent in forest and river area (Kota) and least (3.2%) in semi-arid area (Jaipur). Among rural settings also, desert area showed maximum (25.0%) natural infection in mosquitoes followed by rural setting-1 of semi-arid area (24.1%). Among urban setting of desert area, all the four dengue types viz., DEN-1, 2, 3 and 4 were detected. In semi-arid area, urban settings showed presence of DEN-3, whereas among rural settings, rural-1 showed all the four DEN types, rural-2 showed DEN-1 and DEN-3, rural-4 showed DEN-3 and DEN-4, and rural-3 showed no mosquito infections. In forest and river area, among urban settings only, three DEN types, 1, 2 and 4 were observed. Interpretation & conclusion: In desert and semi-arid areas of Rajasthan, where people possess tendency of over- and sustained storage of domestic water, present observations on occurrence of all four dengue virus types may have important bearing on the epidemiology of DHF in the area.

Positive Rate of Antibody Against Dengue Virus for Korean Who Traveled to Dengue Epidemic Area / 감염과화학요법

BACKGROUND: Recently, dengue fever has increased throughout tropical regions and emerged as the most important vector borne viral disease in human. 4 serotypes of viruses are circulating concurrently in these regions and thus it may be anticipated to increase risk of dengue hemorrhagic fever. Even though dengue fever is still not endemic in Korea, it is necessary to test antibodies against dengue viruses because the number of Koreans who have visited these regions is continuously increasing. MATERIALS AND METHODS: Serum specimens from persons with suspected dengue fever had been collected. Commercial kit, immunochromatographic test (ICA), and the IgM capture enzyme-linked immunosorbent assay (MAC-ELISA) were employed for dengue fever detection in these studies. For confirmation randomized 25 specimens among total of 99 specimens were selected and compared with those results from commercial kit and IFA. RESULTS: 33 (33.3%) among 99 specimens showed positive antibody against dengue virus by commercial kit. Positive rate of traveller who have visited Indonesia, Philippines, Malaysia, Thiland was 54.5%. To compare the efficiency of test methods, 25 randomly selected specimens were tested by the MAC-ELISA and IFA simultaneously. 9 specimens showed postive results with the MAC-ELISA method whereas 13 speciments were positive with the IFA methods. CONCLUSION: Confirming the diagnosis of dengue fever with antibody against dengue virus was attempted for the first time in Korea. The results from our study indicate that establishing a national surveillance and/or laboratory diagnostic system in Korea are necessary. In addtion, antibody test strategies for national surveillance system should be carefully considered.

Positive Rate of Antibody Against Dengue Virus for Korean Who Traveled to Dengue Epidemic Area / 감염과화학요법

BACKGROUND: Recently, dengue fever has increased throughout tropical regions and emerged as the most important vector borne viral disease in human. 4 serotypes of viruses are circulating concurrently in these regions and thus it may be anticipated to increase risk of dengue hemorrhagic fever. Even though dengue fever is still not endemic in Korea, it is necessary to test antibodies against dengue viruses because the number of Koreans who have visited these regions is continuously increasing. MATERIALS AND METHODS: Serum specimens from persons with suspected dengue fever had been collected. Commercial kit, immunochromatographic test (ICA), and the IgM capture enzyme-linked immunosorbent assay (MAC-ELISA) were employed for dengue fever detection in these studies. For confirmation randomized 25 specimens among total of 99 specimens were selected and compared with those results from commercial kit and IFA. RESULTS: 33 (33.3%) among 99 specimens showed positive antibody against dengue virus by commercial kit. Positive rate of traveller who have visited Indonesia, Philippines, Malaysia, Thiland was 54.5%. To compare the efficiency of test methods, 25 randomly selected specimens were tested by the MAC-ELISA and IFA simultaneously. 9 specimens showed postive results with the MAC-ELISA method whereas 13 speciments were positive with the IFA methods. CONCLUSION: Confirming the diagnosis of dengue fever with antibody against dengue virus was attempted for the first time in Korea. The results from our study indicate that establishing a national surveillance and/or laboratory diagnostic system in Korea are necessary. In addtion, antibody test strategies for national surveillance system should be carefully considered.

Seroprevalence of Antibody to Procine Reproductive and Respiratory Syndrome Virus in Diagnostic Submissions

During the period from January to December of 2001, a total of 3,391 swine sera were submitted to our laboratory from 256 farms for the diagnosis of porcine reproductive and respiratory syndrome (PRRS). The antibody to porcine reproductive and respiratory syndrome virus (PRRSV) was tested by the indirect immunofluorescent antibody (IFA) test. Of the 256 farms tested, 230 farms (89.8%) were positive for the PRRSV antibody. The overall seroprevalence of the PRRSV antibody was 52.1% (1765/3391). Most of the pigs seemed to be infected with PRRSV at around 50 to 60 days old. The seroprevalence of the antibody became higher with age, and peaked at around 100 days old. More than one-third of the adult pigs, including boars, gilts, and sows, was positive for the PRRSV antibody. The infection of PRRSV was chronic and confined to growers and/or finishers in most farms. However, the antibody was detected in all production phases at some farms.